Hand-held instrument with extendable shaft locking mechanism

ABSTRACT

An instrument includes a body having an interior conduit. A shaft extends distally out of the body and is movable between a retracted position and an extended position. A locking mechanism that selectively secures the shaft in the retracted and extended positions includes grooves in the body and a locking nut having pins that travel through the grooves to move the locking nut between a locked position and an unlocked position. The locking mechanism also includes compression flanges that flex towards and apply pressure/friction to the shaft when the locking nut is in the locked position and release/reduce the pressure/friction from the shaft when the locking nut is in the unlocked position. The compression flanges restrict the movement of the shaft when the compression flanges are flexed towards, and apply pressure to the shaft.

BACKGROUND 1. Technical Field

This disclosure relates to instruments with extendable shafts. Moreparticularly, the disclosure relates to locking mechanisms for lockingextendable shafts to instruments and in various positions relative tosuch instruments.

2. The Relevant Technology

As is known to those skilled in the art, modern surgical techniquestypically employ radio frequency (RF) power to cut tissue and coagulatebleeding encountered in performing surgical procedures. Electrosurgeryis widely used and offers many advantages including the use of a singlesurgical instrument for both cutting and coagulation. A monopolarelectrosurgical system has an active electrode, such as in the form ofan electrosurgical instrument having a hand piece and a conductiveelectrode or tip, which is applied by the surgeon to the patient at thesurgical site to perform surgery and a return electrode to connect thepatient back to the generator.

The electrode or tip of the electrosurgical instrument is small at thepoint of contact with the patient to produce an RF current with a highcurrent density in order to produce a surgical effect of cutting orcoagulating tissue. The return electrode carries the same RF currentprovided to the electrode or tip of the electrosurgical instrument, thusproviding a path back to the electrosurgical generator.

When an electrosurgical instrument is used for cutting or coagulation,smoke is commonly produced. A surgeon or assistant often uses a separatesmoke evacuation device to remove the smoke from the surgical field.Smoke evacuation devices commonly include a suction wand connected to avacuum device via tubing. The surgeon or assistant holds the suctionwand close to the surgical site and the smoke is drawn into the suctionwand and through the tubing. However, using a smoke evacuation deviceseparate from the electrosurgical instrument is not ideal. Using aseparate smoke evacuation device requires additional hands andinstruments near the surgical site, which can obscure the surgeon's viewof the surgical site and reduce the room available around the surgicalsite for the surgeon to move.

As a result, combination electrosurgical instrument and smoke evacuationdevices have been developed. These combination devices often include ahand piece that can receive an electrode or tip in a distal end thereoffor performing electrosurgical procedures. The hand piece is connectedto a generator via a power cable to convey RF current to the electrodeor tip. Additionally, a smoke evacuation hose is connected between thehand piece and a vacuum to draw smoke away from the surgical site.

Some combination electrosurgical instrument and smoke evacuation devicesinclude an extendable shaft. The electrode or tip can be mounted in thedistal end of the shaft, and the shaft can be extended from the handpiece to increase the reach of the device. The extendable shaft may alsoinclude an open distal end and conduit therethrough to facilitate theevacuation of smoke through the shaft and the hand piece.

Some previous combination devices with extendable shafts include alocking feature for securing the extendable shaft in various extendedpositions. Such devices and features have various shortcomings. Forinstance, when the locking feature is loosened or in an unlockedconfiguration, the extendable shaft can be freely removed from the handpiece. As a result, the device has to be reassembled in order for thedevice to function properly. In some instances, such as during asurgical procedure, having to reassemble the device can create delaysand pose safety risks to the patient. Furthermore, a surgeon or otheroperating room personnel may not know how to properly reassemble thedevice. Moreover, attempts to reassemble the device may result in damageto the device which can render the device inoperable.

The subject matter claimed herein is not limited to embodiments thatsolve any disadvantages or that operate only in environments such asthose described above. Rather, this background is only provided toillustrate one exemplary technology area where some embodimentsdescribed herein may be practiced.

BRIEF DESCRIPTION OF THE DRAWINGS

To further clarify the above and other advantages and features of thepresent invention, a more particular description of the invention willbe rendered by reference to specific embodiments thereof which areillustrated in the appended drawings. It is appreciated that thesedrawings depict only illustrated embodiments of the invention and aretherefore not to be considered limiting of its scope. The invention willbe described and explained with additional specificity and detailthrough the use of the accompanying drawings in which:

FIG. 1 illustrates an exemplary electrosurgical system;

FIG. 2 illustrates an electrosurgical instrument of the system of FIG. 1with an extendable shaft in a retracted configuration;

FIG. 3 illustrates the electrosurgical instrument of FIG. 2 with theextendable shaft in an extended configuration;

FIG. 4 illustrates a cross-sectional view of the electrosurgicalinstrument of FIGS. 2 and 3, showing the extendable shaft in theretracted configuration;

FIG. 5 illustrates a cross-sectional view of the electrosurgicalinstrument of FIGS. 2-4, showing the extendable shaft in the extendedconfiguration;

FIG. 6 illustrates the distal end of the electrosurgical instrument ofFIGS. 2-5, showing a locking mechanism in a locked configuration;

FIG. 7 illustrates the distal end of the electrosurgical instrument ofFIGS. 2-5, showing the locking mechanism in an unlocked configuration;and

FIGS. 8-9 illustrate perspective views of the locking mechanism of FIGS.6 and 7, with a locking nut disconnected;

FIG. 10A illustrates a partial cross-sectional view of the lockingmechanism showing the interior of the locking nut;

10B illustrates a partial cross-sectional view of another embodiment ofa locking mechanism showing the interior of a locking nut;

FIG. 11 illustrates a cross-sectional view of the locking mechanism ofFIGS. 7-10A in an unlocked position;

FIG. 12 illustrates a cross-sectional view of the locking mechanism ofFIGS. 7-10A in a locked position;

FIG. 13 illustrates a partially exploded view a portion of a lockingmechanism according to another embodiment;

FIG. 14 illustrates a perspective view of a locking nut according to anexample embodiment;

FIG. 15 illustrates a cross-sectional view of the locking nut of FIG.14;

FIG. 16 illustrates a cross-sectional view of a locking mechanismincorporating the locking nut of FIGS. 14-15 in an unlocked position;and

FIG. 17 illustrates a cross-sectional view of a locking mechanismincorporating the locking nut of FIGS. 14-15 in a locked position.

DETAILED DESCRIPTION

The present disclosure relates to locking mechanisms for securing anextendable shaft to an instrument and in various positions relative tothe instrument. In some embodiments, the instrument is a hand-heldinstrument, such as an electrosurgical instrument. In other embodiments,the instrument may not include a hand piece or otherwise be specificallydesigned as a hand-held instrument. Rather, the instrument may include abody, an extendable shaft, and a locking mechanism as disclosed herein.

In some embodiments, the extendable shaft may provide functionality toan implement disposed at the distal end of the shaft. For instance, anelectrode tip may be disposed at the distal end of the extendable shaftand electrical current may be communicated to the electrode tip via orthrough the extendable shaft.

In some embodiments, the extendable shaft may provide for the evacuationor delivery of fluid therethrough. For instance, the extendable shaftmay have a conduit extending therethrough, through which smoke or otherfluids may be evacuated away from a surgical site. The conduit may alsobe used to deliver fluid to a surgical site.

Reference is made herein to the evacuation of smoke and components thatfacilitate such function. It will be appreciated that references to“smoke” is merely for simplicity and convenience, and is not intended tolimit the disclosed and claimed embodiments to evacuation of only smoke.Rather, the disclosed and claimed embodiments may be used to evacuatesubstantially any type of fluid, including liquids, gases, vapors,smoke, or combinations thereof. Additionally, rather than simplyevacuating fluid, it is contemplated that at least some of theembodiments may be used to deliver fluids to a desired location, such asa surgical site. Still further, while the illustrated embodimentsinclude smoke evacuation features and capabilities, it will beappreciated that other embodiments of the present disclosure may notinclude smoke evacuation features or capabilities.

FIG. 1 illustrates an exemplary electrosurgical system 100. Theillustrated embodiment includes a signal generator 102, anelectrosurgical instrument 104, and a return electrode 106. Generator102, in one embodiment, is an RF wave generator that produces RFelectrical energy. Connected to electrosurgical instrument 104 is autility conduit 108. In the illustrated embodiment, utility conduit 108includes a cable 110 that communicates electrical energy from generator102 to electrosurgical instrument 104. The illustrated utility conduit108 also includes a vacuum hose 112 that conveys captured/collectedsmoke and/or fluid away from a surgical site. In some embodiments, suchas that illustrated in FIG. 1, cable 110 can extend through at least aportion of vacuum hose 112.

Generally, electrosurgical instrument 104 includes a hand piece 114 andan electrode tip 116. Electrosurgical instrument 104 communicateselectrical energy to a target tissue of a patient to cut the tissueand/or cauterize blood vessels within and/or near the target tissue.Specifically, an electrical discharge is delivered from electrode tip116 to the patient in order to cause heating of cellular matter of thepatient that is in close contact with or proximity to electrode tip 116.The heating takes place at an appropriately high temperature to allowelectrosurgical instrument 104 to be used to perform electrosurgery.Return electrode 106 is connected to generator 102 by a cable 118 inorder to complete the circuit and provide a return electrical path towave generator 102 for energy that passes into the patient's body.

FIGS. 2 and 3 illustrate perspective views of electrosurgical instrument104 separate from the rest of system 100. Hand piece 114 ofelectrosurgical instrument 104 has a proximal end 120 and a distal end122. An extendable shaft 124 is selectively extendable from andretractable into (e.g., translatable along an axis running in theproximal/distal direction) distal end 122. FIG. 2 illustrates extendableshaft 124 in a retracted position where a substantial portion ofextendable shaft 124 is disposed within hand piece 114. Nevertheless, ascan be seen in FIG. 2, a portion of extendable shaft 124 can extend outof hand piece 114 even when shaft 124 is in the retracted position.

In contrast, FIG. 3 illustrates extendable shaft 124 in an extendedposition where a substantial portion of extendable shaft 124 is extendedfrom or disposed outside of hand piece 114. Even when shaft 124 is inthe extended position, a portion of shaft 124 remains disposed withinhand piece 114 so that shaft 124 and hand piece 104 remain connected toone another.

Although not illustrated, extendable shaft 124 can also be extended fromhand piece 114 to various intermediate extended positions between theextended and retracted positions shown in FIGS. 2 and 3. In someembodiments, extendable shaft 124 can be extended to one or morediscreet intermediate extended positions. In such embodiments,extendable shaft 124 and hand piece 114 may include cooperating features(e.g., recesses, protrusions, etc.) that facilitate location ofextendable shaft in the one or more discreet intermediate extendedpositions. In other embodiments, the one or more intermediate positionsmay not be discreet positions. Rather, extendable shaft 124 can beextended to substantially any position between the extended andretracted positions shown in FIGS. 2 and 3.

Extendable shaft 124 can also include a channel or conduit 126 extendingtherethrough. As discussed elsewhere herein, conduit 126 can be used toconvey fluids through instrument 104. For example, smoke or other fluidsat a surgical site can be evacuated through conduit 126. In otherembodiments, fluids (e.g., water, saline, etc.) may be delivered to atarget site through conduit 126.

In the illustrated embodiment, electrode tip 116 is received partiallywithin the distal end of the extendable shaft 124. A portion ofelectrode tip 116 extends from the distal end of shaft 124 so as to beable to interact with patient tissue during an electrosurgicalprocedure. As can be seen in FIGS. 2 and 3, electrode tip 116 is mountedwithin the distal end of shaft 124 such that electrode tip 116 moveswith shaft 124 as shaft 124 is moved between the retracted and extendedpositions.

In some embodiments, such as that shown in FIGS. 2 and 3, the distal endof shaft 124 may be transparent or semi-transparent. For instance, thedistal end of shaft 124 may comprise a nozzle 128 formed of atransparent or semi-transparent material. In other embodiments, morethan just the distal end of shaft 124 can be transparent orsemi-transparent. Making at least the distal end of shaft 124transparent or semi-transparent can provide a surgeon with an increasedfield of view when using instrument 104. For instance, the transparentor semi-transparent portion of shaft 124 may allow a surgeon to see theportion of the surgical field on the opposite side of the shaft 124without requiring the surgeon to move the instrument 104.

As illustrated in FIGS. 2 and 3, hand piece 114 includes a receptacle130 at proximal end 120. Alternative embodiments can include areceptacle on a top and/or side section of a hand piece and/or atdifferent locations along the length of the hand piece (i.e., betweenthe proximal and distal ends thereof). Receptacle 130 can be configuredto have utility conduit 108 (or vacuum hose 112 thereof) (FIG. 1)connected thereto. Receptacle 130 can also be configured to have cable110 (FIG. 1) extend therethrough. In some embodiments, including theillustrated embodiment, receptacle 130 can have an angled configuration.In other embodiments, receptacle 130 can have a straight configuration.Furthermore, in some embodiments, receptacle 130 can be connected tohand piece 114 in a fixed manner. In other embodiments, receptacle 130can be rotatably or pivotally connected to hand piece 114 such that handpiece 114 can rotate or pivot relative to receptacle 130 and utilityconduit 108 or vice versa.

Regardless of the specific configuration of receptacle 130, utilityconduit 108 (or cable 110 or vacuum hose 112 thereof) can be connectedto instrument 104 to provide instrument 104 with certain capabilities orfunctionality. As noted above, for instance, cable 110 can communicateelectrical energy from generator 102 to instrument 104. The electricalenergy can be communicated through instrument 104 to electrode tip 116during an electrosurgical procedure. When vacuum hose 112 is connectedto instrument 104, instrument 104 can be used to evacuate smoke/fluidaway from a surgical site through conduit 126, hand piece 114, andvacuum hose 112.

The operation of instrument 104 can be controlled at least partiallywith one or more controls 132 on hand piece 114. The one or morecontrols 132 enable a user to adjust one or more parameters of theinstrument 104, such as increasing or decreasing electrical powerdelivery through the instrument, turning the instrument on and off,adjusting the instrument for different operating modes (cut, coagulate,cut-coagulate blend), activating a vacuum, etc. For example, thecontrols 132 can provide a connection for transmitting control signalsfrom the instrument 104 to generator 102 and/or a vacuum unit.

Instrument 104 also includes a locking mechanism 134. As will bediscussed in greater detail below, locking mechanism 134 can be used toselectively secure shaft 124 is a desired position relative to handpiece 114. Additionally, locking mechanism 134 can also be selectivelyloosened to allow shaft 124 to be repositioned relative to hand piece114. Furthermore, locking mechanism 134 can also secure shaft 124 tohand piece 114 such that shaft 124 cannot be inadvertently removedentirely from hand piece 114.

Attention is now directed to FIG. 4, which illustrates a cross-sectionalview of instrument 104. FIG. 4 illustrates the extendable shaft 124 in aretracted position, showing that much of the extendable shaft 124 can bepositioned within an interior chamber or conduit 136 of hand piece 114.In the illustrated embodiment, interior conduit 136 is configured insize and shape to enclose extendable shaft 124 (e.g., at least theportions not extending distally beyond hand piece 114) so thatextendable shaft 124 fits within interior conduit 136 and is selectivelytranslatable within interior conduit 136. As shown, interior conduit 136is in fluid communication with the atmosphere exterior to hand piece 114via conduit 126 in shaft 124, enabling the capture of smoke intointerior conduit 136 through conduit 126.

In some embodiments, instrument 104 includes a back stop 138 positionedto limit proximal translation of extendable section 124 within interiorconduit 136. For example, back stop 138 can be disposed at a positionsuch that when extendable shaft 124 is fully retracted, at least nozzle128 and/or electrode tip 116 is at or near the distal portion of handpiece 114 but not retracted into the interior of the hand piece 114.

The illustrated back stop 138 is formed as part of receptacle 130 toprevent proximal movement of extendable shaft 124 past back stop 138.Alternatively, back stop 138 can be formed as a crossbar, wall, rib,detent, abutment, catch, brace, and/or other mechanisms of limitingproximal movement of shaft 124.

In the illustrated embodiment, shaft 124 includes a collet 140 disposedtherein near the distal end of shaft 124. Collet 140 is configured tohave a portion (e.g., a shaft or shank) of electrode tip 116 mountedtherein. With electrode tip 116 mounted in collet 140, a portion ofelectrode tip 116 extends distally from shaft 124 as shown so thatelectrode tip 116 can interact with patient tissue.

In some embodiments, such as the illustrated embodiment, collet 140and/or electrode tip 116 are electrically connected to hand piece 114 byway of a sliding electrical connection. More specifically, hand piece114 includes a conductor 142 disposed on an interior surface of interiorconduit 136. Similarly, extendable shaft 124 includes a slidingconductor 144. Sliding conductor 144 is in electrical contact withconductor 142 and collet 140 and/or electrode tip 116.

Conductor 142 is electrically connected to cable 110 (FIG. 1).Accordingly, electrical energy communicated to instrument 104 via cable110 can be communicated to conductor 142. Electrical energy communicatedto conductor 142 is in turn communicated to collet 140 and/or electrodetip 116. The electrical connection between conductors 142, 144 can bemaintained even when shaft 124 is moved between the retracted andextended positions. In particular, as shaft 124 is moved between theretracted and extended positions, sliding conductor 144 moves with shaft124 and slides along conductor 142 to maintain the electrical connectiontherebetween. As a result electrical energy can be communicated fromcable 110 to electrode tip 116 through the continuous connection betweenconductors 142, 144.

In some embodiments, sliding conductor 144 can be replaced with otherelectrical connections to hand piece 114. For instance, extendable shaft124 may be electrically conductive and able to pass electrical currentto electrode tip 116. For example, electrical energy can be communicatedfrom cable 110 to conductor 142 and then from conductor 142 toelectrically conductive shaft 124 and to electrode tip 116 (directly orthrough collet 140). In such embodiments, extendable shaft 124 may beformed from a conductive material that is at least partially coated witha non-conductive material to prevent the transfer of current fromextendable shaft 124 to patient tissue during an electrosurgicalprocedure.

Alternatively, hand piece 114 and shaft 124 (or collet 140 or electrodetip 116) can be electrically connected with a flexible electrical ribbonto allows shaft 124 to move between the retracted and extended positionswhile maintaining electrical contact between hand piece 114 and shaft124 (or collet 140 or electrode tip 116). In still other embodiments,cable 110 can extend into hand piece 114 and connect directly to shaft124, conductor 144, collet 140, or electrode tip 116.

As shown, extendable shaft 124 can be formed with a length (measuredalong the proximal-distal axis) to be about the same length (e.g.,within 99% of, 95% of, 90% of, 80% of, or 75%) of hand piece 114 inwhich it can selectively translate within. In other embodiments,extendable shaft 124 may be shorter or longer, such as about 0.75 timesor 0.5 times the length of hand piece 114, or about 1.25, 1.5, 2, or 2.5times longer than the length of hand piece 114.

As noted above and as can be seen in FIG. 4, extendable shaft 124includes conduit 126 extending therethrough. Shaft 124 is configured topass at least partially into interior conduit 136 of hand piece 114 suchthat conduit 126 is in fluid communication with conduit 136 and utilityconduit 108 (and/or with vacuum hose 112 thereof). Extendable shaft 124also includes a distal end opening 146 providing fluid communicationbetween conduit 126 and the atmosphere exterior to extendable shaft 124.As shown, electrode tip 116 can be coupled to extendable shaft 124(e.g., via collet 140 or other mechanisms (adhesive, welding, mechanicalfastening, notches, slots, and/or friction fitting, or through integralformation of a single piece)) in a manner that leaves one or moreaperture spaces for smoke capture into conduit 126 of extendable shaft124.

FIG. 5 illustrates instrument 104 with extendable shaft 124 in anextended position. As can be seen, sliding conductor 144 remains inelectrical contact with conductor 142 so that electrical energy can becommunicated to electrode tip 116. Additionally, smoke or other fluidscan be evacuated through conduits 126, 136 in shaft 124 and hand piece114 and out through utility conduit 108 (or vacuum hose 112).

Attention is now directed to FIGS. 6-10, which illustrate lockingmechanism 134 in greater detail. As noted above, locking mechanism 134can selectively secure shaft 124 in a desired position relative to handpiece 114. For instance, locking mechanism 134 can selectively secureshaft 124 in the retracted position (see FIGS. 2 and 4), in the extendedposition (see FIGS. 3 and 5), or in one or more intermediate extendedpositions. Additionally, locking mechanism 134 can be selectivelyunlocked, disengaged, or loosened to enable shaft 124 to move betweenthe retracted and extended positions.

FIG. 6 illustrates locking mechanism 134 in a locked, engaged, ortightened configuration. When locking mechanism 134 is in the locked,engaged, or tightened configuration, shaft 124 is secured in placerelative to hand piece 114. In the illustrated embodiment, lockingmechanism 134 is in the locked, engaged, or tightened configuration whena locking nut 148 is rotated (e.g., about shaft 124) so that locking nut148 is moved proximally relative to hand piece 114.

In contrast, FIG. 7 illustrates locking mechanism 134 in an unlocked,disengaged, or loosened configuration. When locking mechanism 134 is inthe unlocked, disengaged, or loosened configuration, shaft 124 is ableto move relative to hand piece 114 between the retracted and extendedpositions. In the illustrated embodiment, locking mechanism 134 is inthe unlocked, disengaged, or loosened configuration when locking nut 148is rotated (e.g., about shaft 124) so that locking nut 148 is moveddistally relative to hand piece 114.

FIGS. 8-12 illustrate various views of locking mechanism 134. Inparticular, FIGS. 8 and 9 illustrate the distal end of instrument 104with locking nut 148 disconnected from hand piece 114 to show interiorfeatures of locking mechanism 134. Similarly, FIGS. 10A-10B illustratethe distal end of instrument 104 with locking nut 148 disconnected fromhand piece 114 and shown in shown in cross-section. FIGS. 11 and 12 showthe distal end of instrument 104 in cross-section, with the lockingmechanism 134 in the unlocked (FIG. 11) and locked (FIG. 12)configurations.

In the illustrated embodiment, locking nut 148 can slide over the distalend of shaft 124 (e.g., such that shaft 124 extends through locking nut148) and can be secured or connected to hand piece 114. In general, theconnection between locking nut 148 and hand piece 114 is achieved by wayof mating pins and grooves, aspects of which are illustrated in FIGS.8-10B. More specifically, locking nut 148 includes one or moreengagement members, such as pins 150 (FIGS. 9-10A), spaced about itsinterior circumference. Pins 150 are configured and arranged to engagehand piece 114, as discussed below.

In correspondence with pins 150, hand piece 114 includes a collar 152with one or more grooves 154 formed in an outer surface thereof. Thegrooves 154 can extend circumferentially around at least a portion ofcollar 152 and axially along at least a portion of the length of collar152 (e.g., in the proximal/distal direction). The width and depth ofgrooves 154 generally correspond to the diameter and length,respectively, of pins 150. As best illustrated in FIG. 10A, each groove154 includes three connected portions, or segments. Specifically, eachgroove 154 includes an entry segment 156, an intermediate segment 158,and a terminal segment 160. In some alternative embodiments, grooves 154are defined by a structure that is discrete from, but attached orattachable to, hand piece 114.

In the illustrated embodiment, entry segment 156 extends proximally froma distal end of collar 152. In the illustrated embodiment, entry segment156 is generally parallel with the proximal/distal axis of instrument104. In other embodiments, entry segment 156 may extend axially alongand circumferentially about collar 152.

In the illustrated embodiment, entry segment 156 also include aretention feature 162. Retention feature 162 may be configured to allowpin 150 to enter into groove 154 while restricting or preventing removalof pin 150 from groove 154. For instance, retention feature 162 mayinclude an angled surface that allows pin 150 to slide over retentionfeature 162 as pin 150 is introduced into groove 154. Opposite theangled surface, retention feature 162 may include a retention wall thatrestricts or prevents pin 150 from being removed from groove 154.

Intermediate segment 158 is connected to entry segment 156 and extendsproximally and circumferentially from entry segment 156. That is,intermediate segment 158 extends axially along and circumferentiallyabout collar 152. As noted below, the angled orientation of intermediatesegment 158 causes locking nut 148 to move axially relative to handpiece 114.

Terminal segment 160 is connected to intermediate segment 158. As can beseen in FIG. 10A, at least a portion of terminal segment 160 extendsdistally and in a direction generally parallel to the proximal/distalaxis of instrument 104. In other embodiments, terminal segment 160extends axially and circumferentially such that terminal segment 160 andintermediate segment 158 form an acute angle. In either case, aretention ridge 164 is formed between intermediate and terminal segments158, 160. Retention ridge 164 is configured to selectively maintain pin150 in terminal segment 160, thereby preventing locking nut 148 frombeing inadvertently loosened.

In general, the engagement of locking nut 148 and hand piece 114 iseffected by positioning each pin 150 in a corresponding groove 154 andcausing pins 150 to travel along or through grooves 154. Moreparticularly, locking nut 148 and hand piece 114 are brought togetheruntil each pin 150 is positioned in the entry segment 156 of acorresponding groove 150 of hand piece 114. Locking nut 148 is thenadvanced proximally until pins 150 pass over retention features 162 inentry segments 156. When locking nut 148 is so positioned (e.g., withpins 150 in entry segments 156 proximal to retention feature 162),locking mechanism 134 is in the unlocked, disengaged, or loosenedconfiguration as shown in FIG. 7.

Rotation of locking nut 148 (e.g., about shaft 124 or collar 152) isthen initiated. As a result of the angular orientation of intermediatesegments 158 with respect to a longitudinal (proximal/distal) axis ofinstrument 104, the rotation of locking nut 148 causes locking nut 148to be drawn proximally towards hand piece 114. Continued rotation oflocking nut 148 causes pins 150 to travel past retention ridges 164 andinto the terminal segments 160. When locking nut 148 is rotated so pins150 are positioned in terminal segments 160, locking mechanism 134 is inthe locked, engaged, or tightened position as shown in FIG. 6.

To put the locking mechanism 134 in the unlocked, disengaged, orloosened position, locking nut 148 is moved proximally relative to handpiece 114 so as to allow pins 150 to pass over retention ridges 164.Locking nut 148 is then rotated so that pins 150 pass back throughintermediate segments 158 and to entry segments 156. As will beappreciated, the angular configuration of intermediate segments 158causes locking nut 148 to move distally relative to hand piece 114. Asnoted above, retention features 162 can also restrict or prevent pins150 from exiting grooves 154, thereby restricting or preventing lockingnut 148 from being completely disconnected from hand piece 114 whenlocking nut 148 is moved to the unlocked position.

It will be appreciated that the specific configuration and arrangementof the locking mechanism 134 and features thereof as shown in FIGS.8-10A is illustrative only. For instance, FIG. 10B illustrates a lockingmechanism 134A that includes elements that are similar to those oflocking mechanism 134, but in a different configuration or arrangement.In particular, the position of the engagement members or pins and thegrooves are reversed. Accordingly, instead of engagement members or pinsbeing disposed on an interior surface a locking nut, the collar 152Aincludes one or more engagement members or pins 150A disposed on anexterior surface thereof. Similarly, instead of grooves being forming inan exterior surface of a collar, one or more grooves 154A are formed onan interior surface of locking nut 148A.

In the embodiment illustrated in FIG. 10B, locking nut 148A can slideover the distal end of shaft 124 (e.g., such that shaft 124 extendsthrough locking nut 148A) and can be secured or connected to hand piece114. In general, the connection between locking nut 148A and hand piece114 is achieved by in a manner similar to that described above inconnection with FIG. 10A. That is, the pins 150A can be inserted andadvanced through the grooves 154A.

In contrast to groove 154 of FIG. 10A, groove 154A includes: (i) anentry segment 156A extends distally from a proximal end of locking nut148A, (ii) an intermediate segment 158A connected to entry segment 156Aand that extends distally and circumferentially from entry segment 156A,and (iii) a terminal segment 160A connected to intermediate segment158A. As can be seen in FIG. 10B, at least a portion of terminal segment160A extends proximally and in a direction generally parallel to theproximal/distal axis of instrument 104 such that a retention ridge 164Ais formed between intermediate and terminal segments 158A, 160A.

In general, the engagement of locking nut 148A and hand piece 114 iseffected by positioning each pin 150A in a corresponding groove 154A andcausing pins 150A to travel along or through grooves 154A or grooves154A to moves over pins 150 a. More particularly, locking nut 148A andhand piece 114 are brought together until each pin 150A is positioned inthe entry segment 156A of a corresponding groove 150A of in locking nut148A. Locking nut 148 is then advanced proximally until pins 150 passover retention feature 162A in entry segments 156A. When locking nut148A is so positioned (e.g., with pins 150A in entry segments 156Adistal to retention feature 162A), locking mechanism 134A is in theunlocked, disengaged, or loosened configuration as shown in FIG. 7.

Rotation of locking nut 148A (e.g., about shaft 124 or collar 152) isthen initiated. As a result of the angular orientation of intermediatesegments 158A with respect to a longitudinal (proximal/distal) axis ofinstrument 104, the rotation of locking nut 148A causes locking nut 148Ato be drawn proximally towards hand piece 114. Continued rotation oflocking nut 148A causes pins 150A to travel past retention ridges 164Aand into the terminal segments 160A. When locking nut 148A is rotated sopins 150A are positioned in terminal segments 160A, locking mechanism134A is in the locked, engaged, or tightened position as shown in FIG.6.

To put the locking mechanism 134A in the unlocked, disengaged, orloosened position, locking nut 148A is moved proximally relative to handpiece 114 so as to allow pins 150A to pass over retention ridges 164A.Locking nut 148A is then rotated so that pins 150A pass back throughintermediate segments 158A and to entry segments 156A. As will beappreciated, the angular configuration of intermediate segments 158Acauses locking nut 148A to move distally relative to hand piece 114. Asnoted above, retention features 162A can also restrict or prevent pins150A from exiting grooves 154A, thereby restricting or preventinglocking nut 148A from being completely disconnected from hand piece 114when locking nut 148A is moved to the unlocked position.

As the locking nut moves between the locked position (FIGS. 6 and 12)and the unlocked position (FIGS. 7 and 11), the locking nut interactswith compression flanges 166 to either secure shaft 124 in place orallow shaft 124 to move between the retracted and extended positions. Ascan be seen in FIGS. 8-10B, compression flanges 166 extend distally fromcollar 152 and are disposed circumferentially about shaft 124.Additionally, compression flanges 166 are spaced apart from one anothersuch that a gap 168 is disposed between adjacent flanges 166. The gaps168 between compression flanges 166 allow compression flanges 166 to becompressed or flexed inward towards shaft 124 as the locking nut movesfrom the unlocked position to the locked position.

As can be seen in FIGS. 9-12, locking nuts 148, 148A include a taperedinterior surface 170. Surface 170 tapers in the distal direction suchthat surface 170 has a larger diameter at a proximal end than at adistal end. Tapered surface 170 interacts with compression flanges 166to secure shaft 124 in place or to allow shaft 124 to move between theretracted and extended positions.

As can be seen in FIG. 11, when locking nut 148 is in the unlockedposition (e.g., moved distally relative to hand piece 114 so that pins150 are in or near the entry segments 156), the angled configuration oftapered surface 170 allows compression flanges 166 to flex away fromshaft 124. As a result, the friction between compression flanges 166 andshaft 124 is reduced or eliminated, thereby allowing shaft 124 to movebetween the retracted and extended positions.

In contrast, as shown in FIG. 12, when locking nut 148 is moved to thelocked position (e.g., moved proximally relative to hand piece 114 sothat pins 150 are in or near the terminal segments 160), tapered surface170 interacts with compression flanges 166 to flex or compresscompression flanges 166 towards shaft 124. Tapered surface 170 can flexor compress compression flanges 166 against shaft 124 with sufficientforce to secure shaft 124 in place. As a result, shaft 124 can beselectively maintained in a desired position (e.g., retracted,intermediate extended, or extended position).

As noted above, locking mechanism 134 can also prevent shaft 124 frombeing inadvertently removed from hand piece 114. For instance, shaft 124and locking mechanism 134 can have cooperating features to limit thedistal movement of shaft 124 relative to hand piece 114. In theillustrated embodiment, shaft 124 includes a stop 172 (FIGS. 4 and 5) onan exterior surface thereof adjacent to the proximal end of shaft 124.Stop 172 can interact with a shoulder 174 (FIGS. 8-12) on locking nut148 to prevent shaft 124 from being (inadvertently) removed entirelyfrom hand piece 114. By way of example, if locking mechanism 134 ismoved to the unlocked configuration and shaft 124 is moved distallyrelative to hand piece 114, stop 172 will engage shoulder 174 prior toshaft 124 being removed entirely from hand piece 114. Thus, theinteraction between stop 172 and shoulder 174 can prevent a surgeon orother personnel from inadvertently removing shaft 124 from hand piece114 when attempting to adjust the extension of shaft 124 from hand piece114.

Attention is now directed to FIG. 13, which illustrates a lockingmechanism 134 b. Locking mechanism 134 b can be similar or identical tolocking mechanism 134 and can be used with an electrosurgical instrumentsimilar or identical to instrument 106 discussed above. For instance,locking mechanism 134 b includes a collar 152 b adjacent a distal end ofa hand piece 114 b. One or more grooves 154 b may be disposed in collar152 b, similar or identical to grooves 154, for securing a locking nut(e.g., locking nut 148) to collar 152 b in a similar manner as describedabove.

One distinction between locking mechanism 134 b and locking mechanism134 is that compression flanges 166 b are not integrally formed withcollar 152 b or hand piece 114 b. Rather, as illustrated in FIG. 13,compression flanges 166 b (separated by gaps 168 b) are connected to orintegrally formed with a ring 180. Ring 180 is configured to beselectively connected to the distal end of collar 152 b or hand piece114 b. Such connection can take a variety of forms. In the illustratedembodiment, for instance, ring 180 can be connected to collar 152 b orhand piece 114 b via a snap-fit connection. By way of example, anannular groove 182 is formed on an outer surface of the distal end ofcollar 152 b or hand piece 114 b. Ring 180 includes one or morecorresponding detents 184 disposed on a proximal interior surface. Ring180 can be connected to collar 152 b or hand piece 114 b by snappingdetent(s) 184 into groove 182.

In some embodiments, ring 180 can provide a similar function as shoulder174 described above. More specifically, ring 180 can prevent anextendable shaft (e.g., similar to shaft 124) from being inadvertentlyremoved from hand piece 114 b. As noted above in connection with shaft124, an extendable shaft can include a stop (e.g., stop 172) on anexterior surface thereof. The stop can interact with ring 180 to preventthe shaft from being (inadvertently) removed entirely from hand piece114 b. By way of example, if locking mechanism 134 b is moved to theunlocked configuration and an extendable shaft is moved distallyrelative to hand piece 114 b, the stop will engage ring 180 prior to theshaft being removed entirely from hand piece 114 b. Thus, theinteraction between the stop and ring 180 can prevent a surgeon or otherpersonnel from inadvertently removing the shaft from hand piece 114 bwhen attempting to adjust the extension of the shaft from hand piece 114b.

Additionally, the ring 180 can be coupled to collar 152 b or hand piece114 b so as to close off or block an open end of a track 186 formed onthe interior of hand piece 114 b. The track 186 may be configured tohave the stop (e.g., stop 172) on the extendable shaft move therethroughas the extendable shaft is moved between extended and retractedpositions. The open end of the track 186 shown in FIG. 13 may enable thestop to be inserted into the track 186, thereby allowing the extendableshaft to be inserted into the hand piece 114. Once the extendable shaftis inserted into the hand piece 114 b and ring 18 is connect thereto,ring 180 can prevent the stop on the extendable shaft from exiting theend of the track 186. Retaining the stop in the track 186 can preventundesirable rotation of the extendable shaft within hand piece 114 b.

Attention is now directed to FIGS. 14-17 which illustrate anotherexample of a locking mechanism according to the present disclosure.Rather than having compression flanges (e.g., 166, 166 b) integrallyformed with or connected to a collar (e.g., 152, 152 b) or a hand piece(114, 114 b), the illustrated embodiment includes compression flanges166 c integrally formed as part of or connected to a locking nut 148 c.FIGS. 14 and 15 illustrate an end perspective view and a cross-sectionalview of locking nut 148 c. As can be seen, the compression flanges 166 cextend proximally from an interior surface of locking nut 148 c as areseparated by gaps 168 c.

When locking nut 148 c is connected to collar 152 c/hand piece 114 c asshown in FIGS. 16 and 17, the compression flanges 166 c extendproximally towards hand piece 114 c. Additionally, the proximal ends ofcompression flanges 116 c can extend into the distal end of collar 152c/hand piece 114 c between the extendable shaft 124 a and the distal endof collar 152 c/hand piece 114 c. When the locking nut 148 c is in thelocked position as shown in FIG. 16, the compression flanges extenddeeper into collar 152 c/hand piece 114 c. As the compression flanges166 c extend deeper into collar 152 c/hand piece 114 c, the interiorsurface of collar 152 c/hand piece 114 c causes the compression flanges166 c to flex towards shaft 124 a. As the compression flanges 166 c flextowards shaft 124 a, the friction between the compression flanges 166 cand the shaft 124 a increases sufficiently to secure the shaft 124 a inplace.

In contrast, when the locking nut 148 c is in the unlocked position asshown in FIG. 17, the compression flanges are withdrawn at leastpartially from collar 152 c/hand piece 114 c. As the compression flanges166 c are withdrawn from collar 152 c/hand piece 114 c, the interiorsurface of collar 152 c/hand piece 114 c causes the compression flanges166 c to flex towards shaft 124 a to a lesser degree compared to whenthe locking nut 148 c is in the locked position. As a result, thefriction between the compression flanges 166 c and the shaft 124 a isreduced sufficiently to allow the shaft 124 a to move between theextended and retracted positions.

While the embodiments described herein have been directed toelectrosurgical instruments with smoke evacuation features, the presentdisclosure is not intended to be so limited. Rather, the presentdisclosure is broadly directed to any instrument, hand-held or not, thatincludes an extendable shaft. The extendable shaft may increase thereach of the instrument and/or provide fluid evacuation or deliverycapabilities. By way of non-limiting example, such instruments mayinclude dental instruments (e.g., drills, polishing tools, scalers,compressed air tools, suction tools, irrigation tools, carries detectiontools, water flossing tool (e.g., waterpik)), soldering tools (e.g.,heated tools, smoke collection tools, de-soldering tools), high speedgrinding and polishing tools (e.g., Dremel tools, carving tools,manicure tools, dental lab grinders/polishers), laser treatmentinstruments, laser surgical instruments, light probes, suction handles(e.g., Yankauer), blasting tools (e.g., sandblast, gritblast), shockwavetherapy tools, ultrasonic therapy tools, ultrasonic probe tools,ultrasonic surgical tools, adhesive application instruments, glue guns,pneumatic pipettes, welding tools, RF wrinkle therapy devices, phacodevices, shears, shaver, or razor devices, micro drill devices, vacuumdevices, small parts handling devices, tattoo needle handles, smalltorch devices, electrology devices, low speed grinding, polishing andcarving tools, permanent makeup devices, electrical probe devices,ferromagnetic surgical devices, surgical plasma devices, argon beamsurgical devices, surgical laser devices, surgical suction instruments(e.g., liposuction cannulas), surgical suction cannulas,microdermabrasion devices, fiberoptic cameras, microcamera devices, pHprobe devices, fiberoptic and LED light source devices, hydrosurgerydevices, orthopedic shaver, cutter, burr devices, wood burning tools,electric screwdrivers, electronic pad styluses, and the like.

The present invention may be embodied in other specific forms withoutdeparting from its spirit or essential characteristics. The describedembodiments are to be considered in all respects only as illustrativeand not restrictive. The scope of the invention is, therefore, indicatedby the appended claims rather than by the foregoing description. Allchanges which come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

What is claimed is:
 1. An instrument, comprising: a body having aproximal end, a distal end, and an interior conduit defined by aninterior surface, wherein a first portion of the interior surface has afirst cross-sectional dimension along a length of the first portion ofthe interior surface, and wherein a second portion of the interiorsurface has a cross-sectional dimension that increases from the firstcross-sectional dimension adjacent to the first portion to a secondcross-sectional dimension closer to the distal end of the body, thesecond cross-sectional dimension being larger than the firstcross-sectional dimension; an extendable shaft at least partiallydisposed within the interior conduit of the body and extending distallyout of the distal end of the body, the extendable shaft having an outerdimension that generally corresponds to the first cross-sectionaldimension of the interior surface of the interior conduit of the bodysuch that the extendable shaft is selectively movable relative to thebody between a retracted position and an extended position, wherein theincreasing cross-sectional dimension of the interior surface creates agap between a portion of the interior conduit and the extendable shaft,the gap having a dimension that decreases from a larger dimensionadjacent to the distal end of the body to a smaller dimension adjacentthe first portion of the interior surface; and a locking mechanismconfigured to selectively secure the extendable shaft in the retractedand extended positions, the locking mechanism comprising: one or moregrooves associated with the body; a locking nut having one or more pinsthat are configured to travel through the one or more grooves to movethe locking nut between a locked position and an unlocked position, thelocking nut further comprising one or more compression flanges connectedthereto or integrally formed therewith, the one or more compressionflanges being configured to flex towards the extendable shaft when thelocking nut is in the locked position and flex away from the extendableshaft when the locking nut is in the unlocked position, the one or morecompression flanges being configured to restrict movement of theextendable shaft when the one or more compression flanges are flexedtowards the extendable shaft, the one or more compression flanges beingconfigured to extend proximally into the gap between the interiorsurface of the body and an exterior surface of the extendable shaft whenthe locking nut is moved to the locked position.
 2. The instrument ofclaim 1, wherein the extendable shaft comprises a functional implementat a distal end thereof.
 3. The instrument of claim 2, wherein thefunctional implement comprises an electrode tip, the electrode tip beingconfigured to transmit electrical energy to a patient during an electrosurgical procedure.
 4. The instrument of claim 1, wherein the extendableshaft comprises a conduit extending therethrough.
 5. The instrument ofclaim 1, wherein each of the one or more grooves comprises an entrysegment, an intermediate segment, and a terminal segment.
 6. Theinstrument of claim 5, wherein the entry segment extends in a directionparallel to an axis extending between the proximal and distal ends ofthe body.
 7. The instrument of claim 6, wherein the entry segmentcomprises a retention feature configured to enable a pin of the one ormore pins to enter the one or more grooves and prevent inadvertentremoval of the pin from the one or more grooves.
 8. The instrument ofclaim 7, wherein the retention feature comprises an angled surface thatenables the pin to enter the one or more grooves and a retention wallthat restricts movement of the pin out of the one or more grooves. 9.The instrument of claim 5, wherein the intermediate segment is angledsuch that the intermediate segment extends axially along andcircumferentially around at least a portion of the body.
 10. Theinstrument of claim 9, wherein the angled configuration of theintermediate segment causes the locking nut to move proximally ordistally relative to the body as the one or more pins travel through theintermediate segments.
 11. The instrument of claim 5, wherein theterminal segment extends from the intermediate segment in a directiontowards the distal end of the body.
 12. The instrument of claim 5,further comprising a retention ridge formed between the intermediatesegment and the terminal segment, the retention ridge being configuredto selectively retain the pin in the terminal segment.
 13. Theinstrument of claim 1, wherein the body comprises a collar in which theone or more grooves are formed.
 14. The instrument of claim 1, whereinthe interior surface of the interior conduit comprises a taperedinterior surface.
 15. The instrument of claim 14, wherein the taperedinterior surface is configured to interact with the one or morecompression flanges to flex the compression flanges towards theextendable shaft when the locking nut is in the locked position.
 16. Theinstrument of claim 1, wherein the extendable shaft comprises a stopadjacent a proximal end thereof.
 17. The instrument of claim 16, whereinthe locking nut further comprises a shoulder, wherein the stop on theextendable shaft and the shoulder are configured to interact to limitdistal movement of the extendable shaft relative to the body.
 18. Aninstrument, comprising: a body having a proximal end, a distal end, andan interior conduit, the interior conduit comprising an interiorsurface, the interior surface having a first portion with a firstcross-sectional dimension along a length thereof and a second portionwith a cross-sectional dimension that increases from the firstcross-sectional dimension adjacent to the first portion to a secondcross-sectional dimension closer to the distal end of the body, thesecond cross-sectional dimension being larger than the firstcross-sectional dimension; a shaft selectively movable at leastpartially within the interior conduit and relative to the body between aretracted position and an extended position, the shaft having an outerdimension that generally corresponds to the first cross-sectionaldimension of the interior surface of the interior conduit of the body,the shaft comprising a stop adjacent a proximal end thereof, the shaftand the second portion of the interior surface cooperating to form a gaptherebetween, the gap having a dimension that decreases from a largerdimension adjacent to the distal end of the body to a smaller dimensionadjacent the first portion of the interior surface; and a lockingmechanism configured to selectively secure the extendable shaft in theretracted and extended positions, the locking mechanism comprising: alocking nut movably connected to and selectively retained on the body,the locking nut being selectively movable between a locked position andan unlocked position, the locking nut comprising one or more compressionflanges connected thereto or integrally formed therewith, the one ormore compression flanges being configured to extend proximally into thegap between the second portion of the interior surface of the body andthe shaft and that are configured to flex towards and away from theshaft, movement of the locking nut from the unlocked position to thelocked position being configured to move the one or more compressionflanges proximally further into the gap between the second portion ofthe interior surface of the body and the shaft, the one or morecompression flanges being configured to restrict movement of the shaftwhen the one or more compression flanges are flexed towards the shaft,the second portion of the interior surface being configured to flex theone or more compression flanges towards the shaft when the locking nutis moved to the locked position, the stop being configured to preventcomplete removal of the shaft from the body.
 19. The instrument of claim18, wherein the one or more compression flanges are disposedcircumferentially about the shaft.
 20. An electrosurgical instrument,comprising: a hand piece having a proximal end, a distal end, and aninterior conduit defined by an interior surface, the interior surfacecomprising a first portion having a first cross-sectional dimensionalong a length of the first portion and a second portion having across-section dimension that increases from the first cross-sectionaldimension adjacent to the first portion to a second cross-sectionaldimension adjacent to the distal end of the hand piece; a utilityconduit connected to the hand piece, the utility conduit comprising acable configured to communicate electrical energy to the electrosurgicalinstrument and a vacuum hose in fluid communication with the interiorconduit; a shaft disposed at least partially within the interior conduitof the hand piece and having an outer dimension that generallycorresponds to the first cross-sectional dimension of the interiorsurface of the interior conduit of the hand piece such that the shaft isselectively extendable from the hand piece between a retracted positionand an extended position, the shaft having a conduit therethrough thatis in fluid communication with the interior conduit, an exterior surfaceof the shaft and the second portion of the interior surface of theinterior conduit cooperating to form a gap between the interior conduitand the shaft, the gap having a dimension that decreases from a largerdimension adjacent to the distal end of the hand piece to a smallerdimension adjacent the first portion of the interior surface; anelectrode tip mounted in a distal end of the shaft, the electrode tipbeing configured to provide electrical energy to a target tissue; and alocking mechanism configured to selectively secure the shaft in theretracted and extended positions, the locking mechanism comprising: oneor more grooves associated with the hand piece, each of the one or moregrooves comprising an entry segment, an intermediate segment, and aterminal segment; a locking nut comprising: one or more pins that areconfigured to travel through the one or more grooves to move the lockingnut between a locked position and an unlocked position; and one or morecompression flanges that are configured to flex towards the shaft whenthe locking nut is in the locked position and flex away from the shaftwhen the locking nut is in the unlocked position, the one or morecompression flanges being configured to restrict movement of the shaftwhen the one or more compression flanges are flexed towards the shaft,wherein the one or more compression flanges are configured to extendproximally into the gap between the second portion of the interiorsurface of the hand piece and the exterior surface of the extendableshaft when the locking nut is moved from the unlocked position to thelocked position; one or more retention features that restrict removal ofthe one or more pins from the one or more grooves; and one or moreretention ridges that selectively maintain the one or more pins in theterminal segment of the one or more grooves.